Prevention of intraventricular hemorrhage during CSF shunt revisions by means of a flexible coagulating electrode. A preliminary report

We report the preliminary results of a prospective study in 19 patients (22 procedures) undergoing ventricular catheter replacement at the time of CSF shunt revision to determine the value of intraluminal coagulation by means of a flexible monopolar coagulating electrode in preventing ventricular hemorrhage following catheter removal. These patients had their first shunt implanted during infancy, and underwent shunt revision during the 1-year period between October 1996 and October 1997. Sixteen patients were found to have adherent ventricular catheters, that necessitated the use of diathermy for their removal. In 10 procedures electrocoagulation was applied to the stylet of the ventricular catheter thus permitting tube extraction. In the remaining 8 shunt revisions catheter removal was readily accomplished by coagulation applied to a flexible monopolar endoscopic electrode introduced into the lumen of the tube. Two patients developed mild intraventricular hemorrhage following the use of each of the two methods described above. Both coagulation techniques used during the routine withdrawal of ventricular catheters seem to be equally effective. The flexible coagulating electrode has the additional advantage over the stylet of being moldable, allowing its use in cases in which the catheter does not follow a straight course within the ventricular cavity.     

Successful treatment of postoperative right ventricular heart failure with the HIA-Medos-assist system in a 2-year-old girl

Communicating hydrocephalus can be handled either by the ventriculoperitoneal or, occasionally, the ventriculoatrial shunt. The lumboperitoneal shunt is another option. It does not require a transcranial approach; therefore, it is safer for the patient. We describe a technique that can be performed easily by a skilled laparoscopic surgeon through an anterior approach transabdominally. The lumboperitoneal (LP) shunt is placed laparoscopically under direct videoscopic vision, with the catheter inserted transabdominally through the L3 disc space into the thecal sac. In our patient, the lumboperitoneal shunt was placed at the L3 disc space for communicating hydrocephalus. There were no intraoperative or postoperative complications. The LP shunt can be easily placed by a skilled laparoscopic surgeon. The incidence of infection and complications is lower, and the patency rate is higher. This should be the initial choice for communicating hydrocephalus.     

In vitro and in vivo efficacy of a rifampin-loaded silicone catheter for the prevention of CSF shunt infections

Infection of cerebrospinal fluid (CSF) shunts is one of the major complications associated with their use and is usually managed by shunt removal, temporary insertion of an external drainage and implantation of a new shunt system. We have evaluated the efficacy of a rifampin-loaded silicone ventricular catheter to prevent bacterial colonization and infection in vitro and in an animal model. On the basis of an incorporation process a rifampin-loaded catheter was developed which is capable of releasing rifampin in bacteriocidal concentrations for 60 days and more. In a stationary bacterial adherence assay using S. epidermidis as test strain, the colonization resistance of the device was demonstrated. To assess the capability of the catheter to prevent CSF shunt infections, a rabbit model was developed which allowed the establishment of a reliable and reproducible CSF infection by implantation of silicone catheters into the ventricle and inoculating S. epidermidis (minimal dose 10(6) cfu) or S. aureus (minimal dose 10(3) cfu). Rifampin-loaded catheters (12 animals inoculated with S. epidermidis, 8 animals inoculated with S. aureus) were compared with non-loaded (14 animals inoculated with S. epidermidis, 19 animals inoculated with S. aureus) control catheters, and infection was documented by clinical, microbiological and histological methods. In contrast to the control group, none of the animals with rifampin-loaded catheters showed clinical signs of infection. Furthermore, in none of the materials obtained after sacrifice of the animals (catheter, brain tissue, CSF, blood) could the infecting bacteria be cultured, whereas in materials from animals with the unloaded catheter the infecting strains could always be cultured from the catheter and from surrounding brain tissue. The histological examination of catheter-adjacent tissue supported these findings. We conclude that a rifampin-loaded silicone ventricular catheter is capable of completely preventing bacterial colonization and infection by staphylococci as the main causative organisms in CSF shunt infections and should be further evaluated in clinical trials.     

Temporary shunt system with a heparin-coated inner surface for interruption of cerebral circulation: experiments in primates

OBJECTIVE: Temporary interruption of the cerebral circulation is sometimes required during the course of neurosurgical procedures. It would be beneficial to develop some type of vascular shunt system that could be used when temporary interruption of the cerebral circulation is necessary. Recent advances in the production of hemocompatible materials suggested to us that it would be possible to develop a small caliber temporary shunt system. METHODS: We developed and investigated in primates a small caliber, temporary arterial shunt system. The heparin-coated shunt catheter was 30 cm in length and had an internal diameter of 1.2 mm. Five Japanese monkeys were used for these experiments. Flow was maintained for 3 hours through a shunt connecting the radial and carotid arteries. We investigated the following: 1) biocompatibility of the catheter, 2) patency of the system, 3) flow through the system, 4) histology of the inner surface of the catheter, 5) biochemical analysis of blood components adhering to the inner surface of the catheter, and 6) histology of perfused brain. RESULTS: Angiography performed through the shunt showed adequate distal cerebral perfusion. Flow through the catheters was 47+/-1.7 ml per minute. Analysis of the shunt catheter at the conclusion of the perfusion period showed no clot formation in the lumen by gross inspection or electron microscopy. CONCLUSION: This system could prove useful for preventing cerebral ischemia during the course of neurosurgical procedures in which the cerebral circulation must be temporarily interrupted.     

Clinically aggressive metastasizing pleomorphic adenoma: report of two cases

Described are 3 cases of a disconnected ventriculoperitoneal shunting system that was successfully retrieved by using a laparoscopic procedure, with a review of the literature. All patients had symptoms of increased intracranial pressure. Roentgenograms showed disconnection of a ventriculoperitoneal shunt catheter at the connecting device and its migration into the peritoneal cavity. A laparoscope was introduced into the peritoneal cavity using the double puncture procedure and the catheter was extracted in less than 15 minutes. The use of a laparoscope enabled exploration of the entire space of the cavity without any large laparotomy incision. Furthermore, the laparoscopic procedure also easily enabled introduction of a replaceable ventriculoperitoneal shunt catheter into the appropriate portion in the cavity and confirmed the CSF flow into the cavity. Because catheters which have migrated into the cavity might cause an acute abdomen, it is important that they should be removed as soon as possible. It should be kept in mind, during the procedures of extracting catheters, that the inner absorptive surface of the peritoneal cavity must be preserved as much as possible. In this regard, laparoscopic retrieval of disconnected shunt catheters is a promising method.     

Lymphocytic choriomeningitis virus-induced alterations of T helper-mediated responses in mice developing autoimmune hemolytic anemia during the course of infection

A slit-like ventricle is one of the serious complications which can occur after a shunting operation. Low pressure valve systems are usually applied for hydrocephalus during infancy. As a result the shape of the ventricle often becomes slit-like after the operation. Many shunt dependent children with slit-like ventricles have to undergo shunt revisions repeatedly. From April 1995 to February 1997 the authors used the Medos programmable Hakim valve system for 20 hydrocephalic children with slit-like ventricles who had been suffering from multiple shunt problems. The patients ages at the operation were between 3-16 Male:Female was 12:8. Follow up periods were 10-20 months. In 12 of 20 patients the shunt revisions were performed at the time of shunt dysfunction and the valve pressure levels were able to be set at the highest levels without the appearance of any symptoms. In this group the size of all the ventricles had become slightly enlarged. In the other 8 patients the operations were performed for fear of other troubles arising if shunt revisions were neglected. In this group the valve pressure levels were set with reference to the intraoperative ICP. It took a relatively long period to elevate the valve levels. Shunt dysfunction due to obstruction of the ventricular catheter was seen in one case but the symptom was not so severe and the catheter which had firmly adhered to the choroid plexus was removed endoscopically. In 2 cases of this series the shunt systems were successfully eliminated. The authors report the method and efficacy of their series using the Medos programmable Hakim valve system and a newly developed ventriculofiberscope for the slit-like ventricle of children.     

Catheter infection in intensive care: influence of systematic replacement of central venous catheters on a guide wire every 4 days

OBJECTIVES: Determine whether systematic replacement of central venous catheters on a guide wire every 4 days leads to a lower rate of catheter infection. METHODS: We conducted a prospective randomized study comparing systematic catheter replacement with the standard procedure where one-way catheters are left in situ as needed. RESULTS: The study included 150 patients and 170 catheters. Catheter replacement on a guide wire was performed 169 times. The rate of infection was not significantly different between the group of patients with replacement (3.7 for 1000 catheter days) and the group with systematic replacement (5.4 for 1000 catheter days). No mechanical complications occurred during the replacement procedures on guide wires. CONCLUSION: We do not recommend systematically replacing catheters on a guide wire for the prevention of catheter infection. This procedure may however be indicated in case of suspected catheter infection as no mechanical of infectious complications occurred.     

Confocal laser scanning microscopy of peritoneal catheter surfaces

Surface topography of used (in situ > 12 months) and unused CAPD catheters was studied by scanning electronmicroscopy (SEM) and confocal laser scanning microscopy (CLSM). Microbial biofilm was observed on all used catheters. Disruption and removal of the attached biofilm revealed extensive pitting of the catheter surface and scoring within the catheter pores. Similar, though less extensive, surface defects were present in unused catheters. Examination by CLSM, with software specific to the determination of surface topography, showed used catheters to have a surface microrugosity greater than that of unused catheters (p < 0.0005). Adherence studies with radiolabelled Staphylococcus epidermidis demonstrated increased adherence to used than to unused catheters (p < 0.0005) after 48 h. However, when catheters were pre-treated with spent dialysate there was a substantial reduction in bacterial adherence to either catheter and no significant difference in adherence to used and unused catheters. Surface microrugosity of CAPD catheters increases during use but is unlikely to be an important factor in bacterial adherence in vivo.     

Frequency and causes of shunt revisions in different cerebrospinal fluid shunt types

Shunt complications and revisions are common in hydrocephalic patients treated with a ventriculo-atrial or a ventriculo-peritoneal shunt. The reported revision rate differs very much but the rate of revision is close to 50% in many papers. Data from 884 hydrocephalic patients treated with various shunt types in the period 1958-1989 were recorded retrospectively in order to evaluate the frequency of revision for various shunt types and secondly to analyse the specific reasons for the shunt revisions. The rate of shunt revision was 45%. The Pudenz shunt was revised more often (62%) than the remaining shunt types. The Hakim and the Orbis-Sigma shunts had fewer revisions (35% and 27%, respectively) than the other observed shunt types. A defect of or an obstruction in the ventricular catheters was a frequent cause of revision followed by a defect or an obstruction of the distal catheter, a displacement of the distal catheter and an acute infection. Because of the higher rate of revision for the Pudenz shunt the rate of the above mentioned specific complications is also higher in most of the subgroups for that specific shunt type. Driven by these experiences it is reasonable to seek to develop and introduce new shunt types in an attempt to reduce the complication rate.     

Experience with use of extended length peritoneal shunt catheters

The placement of a ventriculoperitoneal (VP) shunt is the current treatment of choice for diversion of cerebrospinal fluid associated with hydrocephalus. Although there are a host of reported potential abdominal complications related to the procedure, they are notably uncommon. The authors report their experience with the primary insertion of an extended length open-ended peritoneal tubing (120 cm) undertaken expressly to avoid the need for a lengthening procedure because of growth of the patient. In a review of new insertions of VP shunts using the extended length tubing over a 14-year period at Childrens Hospital of Los Angeles, a total 998 shunts were placed in 952 patients, with a mean follow-up period of 6.7 years. The patients experienced a total of 52 distal shunt revisions for a variety of malfunction etiologies. In patients ranging in age from premature neonate to 20 years, there was no increase in the distal complication rate, and specifically no complications were experienced that were directly related to the use of the extended length tubing. The authors conclude that the use of an extended length peritoneal shunt catheter is not associated with an increase in complications and eliminates the need to lengthen the peritoneal catheter for growth of the patient.     

In vivo evaluation of the new antithrombogenic reservoir-catheter coated with polymer blend copolymer

We evaluated the antithrombogenicity of 4F-catheters coated with the new antithrombogenic material fluorine-acryl- styrene-urethane-silicone (FASUS) graft-block copolymer by dissecting microscopic and scanning electron microscopic observations. These catheters were temporarily used for the infusa-A-port, which was prepared for the treatment of four patients with bladder cancer. Two heparin-coated catheters were also evaluated. All FASUS-coated catheters contained thrombi consisting of red thrombi and/or fibrin thrombi. Massive red thrombus was seen at the site of curvature of the catheters, 1 cm distal to the tip of the catheter. However, the portion 20 cm distal to the tip of the catheter had no red thrombus, but contained minimal fibrin thrombus or plasma protein. The heparin-coated catheters showed the same findings as the FASUS catheters. The FASUS-coated catheters were not superior in antithrombogenicity to the heparin-coated catheters. It was concluded that the FASUS-coated catheters used in this study seemed to have problems in regard to their preshaped curvature and the material used in catheter. These aspects need to be improved.     

Effects of gallstone solvents on commonly used catheters

PURPOSE: To determine what interaction and effect different cholesterol gallstone solvents have on catheters used for gallstone chemolysis. MATERIALS AND METHODS: Five types of catheters used for biliary procedures were chosen: polyethylene, Percuflex, silicon, Silitek, and polyurethane. The solvents chosen were methyl tert-butyl ether, ethyl propionate, isopropyl acetate, and N-propyl acetate. After incubation of the catheters in the solvents for 72 hours, they were air dried. Weight and area changes were determined for each catheter. Additionally, carbon-13 nuclear magnetic resonance (NMR) spectroscopy was performed for analysis of composition changes. RESULTS: Three catheters--silicone, Silitek, and polyurethane--showed changes in their physical characteristics that would make them less desirable for stone chemolysis. The silicone catheter showed changes in elastic texture as well as marked weight reduction. The Silitek and polyurethane catheters had similar, but less dramatic changes. C-13 NMR analysis of collected solvents showed that commonly used plasticizers were leached out of some catheters. CONCLUSION: These results suggest that all catheters are not suitable for use with all solvents. The choice of catheter should be made based on the solvent in use. The polyethylene catheter performed best under the conditions and endpoints used in this study.     

Choroid plexus cyst of the left lateral ventricle with intermittent blockage of the foramen of Monro, and initial invagination into the III ventricle in a child

A cyst of the choroid plexus of the left lateral ventricle with intermittent blockage of the foramen of Monro and initially with invagination of the III ventricle in a child is described. In a 6-week-old boy a ventriculoatrial shunt was implanted for correction of an active asymmetrical hydrocephalus of unknown origin. When he was 3 months of age a water-soluble contrast CT ventriculography revealed a noncolloid cyst localised predominantly in the upper portion of the III ventricle. At that time the ventricular catheter obstructed with choroid plexus was removed; new bilateral catheters in a parieto-occipital region were implanted. In the course of the next 4 years, first the atrial catheter had to be extracted and then the peritoneal catheter was changed, in both cases because of obstruction. Periods of normal life alternated with periods of transient and intermittent symptoms of increased intracranial pressure, papilloedema, and myoclonic jerks. Repeated computed tomography (CT) and magnetic resonance imaging (MRI) showed stabilised hydrocephalus with an enlarged left lateral ventricle. When the boy was 16 years old MRI revealed a choroid plexus cyst in the left lateral ventricle 2 cm in diameter, with a ballvalve type of obstruction of the foramen of Monro. CT stereoendoscopic resection of the wall of a large cyst filled with cerebrospinal fluid was performed, and two additional adnexal small cysts were coagulated using the bipolar coagulator, Diomed 25 laser and scissors; the symptoms then regressed, except for superior bilateral altitudinal anopsia. Light and electron microscopy of the cyst wall is reported. The cyst was composed of collagenic connective tissue lined with a basal lamina lacking in epithelial cells. The preoperative and postoperative MRI are presented. Choroid plexus cysts localised in the anterior part of lateral ventricles are very rare, and all reported cases have been in male patients. According to the literature our case is only the third ever described in a child.     

The role of endoscopic third ventriculostomy in the management of shunt malfunction

OBJECTIVE: To evaluate the effectiveness of third ventriculostomy as an alternative to shunt revision in the management of shunt malfunction and infection in obstructive hydrocephalus. METHODS: All of the clinical notes of 30 patients treated with third ventriculostomy for malfunctioning or infected shunts between January 1, 1974, and December 31, 1996, were retrospectively reviewed. Third ventriculostomy was performed under fluoroscopic control in the first seven patients and endoscopically in the remainder. A successful outcome was achieved if further shunt revision surgery was avoided. The median follow-up duration was 8.7 years RESULTS: Twenty-three patients (76.7%) experienced successful outcomes, resulting in shunt independence. Of the seven failures, three were technical failures at the time of surgery and the remaining four were manifest within a median of 10 days, resulting in shunt revision. There have been no delayed failures. CONCLUSION: Third ventriculostomy is a valuable alternative to shunt revision in patients affected by obstructive hydrocephalus presenting with shunt malfunction or infection. It should be considered in all suitable cases as the first-line treatment for obstructive hydrocephalus of all causes. Because all failures were manifest within a short time, it is likely that these successes will be durable.     

Epilepsy in children with shunted hydrocephalus

OBJECT: The incidence of epilepsy among children with hydrocephalus and its relation to shunts and their complications, raised intracranial pressure (ICP), and developmental outcome are explored in a retrospective study. METHODS: The authors studied a series of 802 children with hydrocephalus due to varying causes, who were treated by ventriculoperitoneal shunt placement between 1980 and 1990, with a mean follow-up period of 8 years. Patients who had tumoral hydrocephalus and those whose files lacked significant data were excluded. Data extracted from medical records, including history of the hydrocephalus and history of seizures, if any, were analyzed. Thirty-two percent of the children had epilepsy, the onset of which frequently occurred at approximately the same time that the diagnosis of hydrocephalus was made. The majority of the affected children had severe uncontrolled epilepsy. The incidence of epilepsy was significantly affected by the original cause of the hydrocephalus. The presence of radiological abnormalities was also found to be a significant predictor of epilepsy. Similarly, shunt complications predisposed to epilepsy. Episodes of raised ICP related to hydrocephalus or in association with shunt malfunction may also predispose to epileptic seizures. Furthermore, the presence of a shunt by itself seems able to promote an epileptogenic focus. Finally, epilepsy appears to be an important predictor of poor intellectual outcome in hydrocephalic children with shunts. CONCLUSIONS: A prospective study is needed to identify clearly and confirm avoidable factors predisposing to seizures in these children so that we can strive to reduce the incidence of these seizures and, subsequently, improve these children's quality of life.     

Safety and efficacy of hydrogen peroxide plasma sterilization for repeated use of electrophysiology catheters

OBJECTIVES: The purpose of this study was to evaluate a new technique for sterilizing nonlumen electrophysiology catheters that uses hydrogen peroxide gas plasma. BACKGROUND: The reuse of electrophysiology catheters may potentially result in a significant cost savings. While ethylene oxide sterilization appears to be safe and effective from a clinical standpoint, toxic ethylene oxide residuals, which exceed Food and Drug Administration standards, have been reported. METHODS: Ten nonlumen electrophysiology catheters were extensively evaluated. Each catheter was used five times and resterilized after each use with hydrogen peroxide gas plasma. Tests for sterility, mechanical and electrical integrity, chemical residuals and standard and electron microscopic inspection were performed. RESULTS: Loss of electrical integrity or mechanical integrity was not observed in any catheter. No evidence of microbial contamination was found. Surface integrity was preserved except for one ablation catheter that exhibited fraying of the insulation at the insulation-electrode interface. Surface inspection using standard magnification and electron microscopy revealed no significant change in surface characteristics associated with the sterilization process. Hydrogen peroxide was the only chemical residual noted, with an average concentration of 0.22% by weight, which is within accepted American Association for the Advancement of Medical Instrumentation limits. The cost for a standard electrophysiology catheter ranges from $200 to $800, and one sterilization cycle costs $10. If electrophysiology catheters are used five times, resterilization could potentially result in a savings of $2,000 per catheter, or $9,000 for five ablation procedures. CONCLUSIONS: Hydrogen peroxide gas plasma sterilization may provide a cost-effective means of sterilizing nonlumen electrophysiology catheters without the problem of potentially harmful chemical residuals. However, careful visual inspection of catheters, particularly at the insulation-electrode interface, is required if catheter reuse is performed.     

The effects of detergents on t-butyl hydroperoxide-induced chemiluminescence

Subcutaneous central venous infusion reservoirs (central venous catheters) are one of the primary devices for administration of intravenous chemotherapy. Usually these devices have few problems, and they provide dependable long term central venous access. Infection of these catheters is a significant problem that usually requires removal. When infection is suspected, it is often difficult to make this determination without actually removing the catheter. Thorough preoperative evaluation may help the surgeon decide which catheters are infected and should be removed. A total of 817 subcutaneous infusion reservoirs were placed at our institution from January 1, 1990 through November 1, 1994. During the same time period, 143 catheters were removed, 63 for suspected infection. The charts of these 63 patients were reviewed to determine to what extent available preoperative information could be used to predict which catheters were infected, thus avoiding unnecessary removal. Twenty-three preoperative parameters were assessed, including physical exam, body temperature, leukocyte count, platelet count, blood cultures from the catheter and peripheral blood, time from placement to removal, whether or not the catheter was functional, and whether it was currently in use. Forty catheters (65%) removed for suspected infection were infected, as demonstrated by a positive culture from the catheter or the wound. Staphylococcus was the most common microorganism. Physical exam (local erythema, tenderness, or swelling) correlated significantly with catheter infection (P = 0.0238). In contrast, blood culture data and the other clinical and laboratory parameters showed no significant association with catheter infection. We conclude that physical exam is the best indicator of catheter infection. Commonly used parameters such as fever, leukocytosis, and positive blood cultures are nonspecific, may not be due to catheter infection, and were not significant in our study. Removal and subsequent restoration of long term intravenous access is associated with significant morbidity and expense. Clinical decision making should not be based on isolated laboratory findings, but must be individualized in each patient with suspected catheter infection.     

Analytical and biologic variability in measures of hemostasis, fibrinolysis, and inflammation: assessment and implications for epidemiology

CONTEXT: Central venous catheters impregnated with chlorhexidine and silver sulfadiazine have recently been introduced for the prevention of catheter-related infections. However, there remains some uncertainty regarding the efficacy of these catheters because of conflicting reports in the literature. OBJECTIVE: To evaluate the efficacy of chlorhexidine-silver sulfadiazine-impregnated central venous catheters in the prevention of catheter-related bloodstream infection. DATA SOURCES: Studies identified from a computerized search of the MEDLINE database from January 1966 to January 1998, reference lists of identified articles, and queries of principal investigators and the catheter manufacturer. STUDY SELECTION: Randomized trials comparing chlorhexidine-silver sulfadiazine-impregnated central venous catheters with nonimpregnated catheters were included. The outcomes assessed were catheter colonization and catheter-related bloodstream infection confirmed by catheter culture. DATA EXTRACTION: Twelve studies met the inclusion criteria for catheter colonization and included a total of 2611 catheters. Eleven studies with a total of 2603 catheters met the inclusion criteria for catheter-related bloodstream infection. Most patients in these studies were from groups considered to be at high risk for catheter-related infections. Summary statistics were calculated using Mantel-Haenszel methods under a fixed-effects model. DATA SYNTHESIS: The summary odds ratio for catheter colonization was 0.44 (95% confidence interval [CI], 0.36-0.54; P<.001), indicating a significant decrease in catheter colonization associated with impregnated catheters. The studies examining the outcome of primary interest, catheter-related bloodstream infection, had a summary odds ratio of 0.56 (95% CI, 0.37-0.84; P = .005). CONCLUSIONS: Central venous catheters impregnated with a combination of chlorhexidine and silver sulfadiazine appear to be effective in reducing the incidence of both catheter colonization and catheter-related bloodstream infection in patients at high risk for catheter-related infections.     

Randomized trial of cerebrospinal fluid shunt valve design in pediatric hydrocephalus

OBJECTIVE: Forty percent of standard cerebrospinal fluid shunts implanted for the treatment of pediatric hydrocephalus fail within the first year. Two new shunt valves designed to limit excess flow, particularly in upright positions, were studied to compare treatment failure rates with those for standard differential-pressure valves. METHODS: Three hundred-forty-four hydrocephalic children (age, birth to 18 yr) undergoing their first cerebrospinal fluid shunt insertion were randomized at 12 North American or European pediatric neurosurgical centers. Patients received one of three valves, i.e., a standard differential-pressure valve; a Delta valve (Medtronic PS Medical, Goleta, CA), which contains a siphon-control component designed to reduce siphoning in upright positions; or an Orbis-Sigma valve (Cordis, Miami, FL), with a variable-resistance, flow-limiting component. Patients were monitored for a minimum of 1 year. Endpoints were defined as shunt failure resulting from shunt obstruction, overdrainage, loculations of the cerebral ventricles, or infection. Outcome events were assessed by blinded independent case review. RESULTS: One hundred-fifty patients reached an endpoint; shunt obstruction occurred in 108 (31.4%), overdrainage in 12 (3.5%), loculated ventricles in 2 (0.6%), and infection in 28 (8.1%). Sixty-one percent were shunt failure-free at 1 year and 47% at 2 years, with a median shunt failure-free duration of 656 days. There was no difference in shunt failure-free duration among the three valves (P = 0.24). CONCLUSION: Cerebrospinal fluid shunt failure, predominantly from shunt obstruction and infection, remains a persistent problem in pediatric hydrocephalus. Two new valve designs did not significantly affect shunt failure rates.     

Hydrocephalus secondary to diffuse villous hyperplasia of the choroid plexus. Case report and review of the literature

Diffuse villous hyperplasia of the choroid plexus, which is distinct from bilateral choroid plexus papillomas, is extremely rare and is often associated with hydrocephalus due to the overproduction of cerebrospinal fluid (CSF). The authors describe an infant with hydrocephalus, diagnosed by computerized tomography scanning, who developed ascites following placement of a ventriculoperitoneal shunt and, subsequently, demonstrated excessive CSF production when the shunt was externalized. The patient was later successfully treated by placement of a ventriculoatrial shunt. Magnetic resonance imaging demonstrated diffuse villous hyperplasia of the choroid plexus as the cause of the patient's hydrocephalus. The literature on diffuse villous hyperplasia of the choroid plexus is reviewed.